1. Field of the Invention
The present invention relates to a rubber composition, more specifically, relates to a rubber composition having improved heat buildup resistance and scorch resistance by the combined use of the specific compounding agents.
2. Description of the Related Art
In the past, as a rubber reinforcing filler for giving a low heat buildup and improving the abrasion resistance, carbon black surface-treated with an organic silicon compound was proposed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 10-46047, Japanese Unexamined Patent Publication (Kokai) No. 11-116841, etc. Further, as the surface-treated carbon black for improving these functions, carbon black surface-treated with a silane coupling compound having an amino group is proposed by Japanese Unexamined Patent Publication (Kokai) No. 9-87612. Further, the present inventors found that the heat buildup resistance and abrasion resistance of a rubber compound are improved by simultaneously blending of carbon black treated with a silane compound having an amino group and a silane coupling agent containing sulfur. However, this causes a problem of a poor scorch resistance.